For much of the 20th century, advancements in anesthesia and infection control allowed surgeons to be maximally invasive; as a result, all surgical specialties advanced leaps and bounds. Starting towards the end of the last century, one started to question whether the same clinical results could be achieved through minimally invasive methods, which led to the development of laparoscopic surgery and other types of minimally invasive surgery (MIS). The applications of MIS in the cranial space (endoscopic neurosurgeries) pose unique problems such as: a) the need to minimize the number of transgressions through the brain parenchyma because any movements of the instruments that transgress the brain parenchyma would result in collateral damage, b) lack of large surgical spaces, and c) restricted access for the assistant. These restrictions are accentuated in the pediatric population, yet one may convincingly argue that these pediatric patients stand to benefit the most from the MIS methods. Current steerable endoscopic tools, in commercial and research, are not less than 2mm in diameter and lack bimanual triangulation capabilities. A breakthrough in instrumentation design will undoubtedly increase the ability of surgeons to treat complex diseases via endoscopic surgeries. Thus, the overall goal of this project is to design, develop, and evaluate modular, steerable, and flexible robotic endoscopic tools with high fidelity force feedback and intrinsic shape sensing capability that can be introduced through a two- channel MINOP endoscope (commonly used in neurosurgery) and to improve the current work-flow in the operating theater. We will thus address two specific aims in this project: Sp. Aim 1 (Georgia Tech): Develop hand-held, modular, steerable robotic endoscopic tools with in-line high fidelity force feedback and intrinsic shape sensing capability, that are easily interchangeable during endoscopic surgery. Through laser and other micromachining/finishing techniques, high quality features of different shapes (notches) and sizes (10-100 microns) at the distal end of endoscopic tools to achieve steerability, will be realized. Sp. Aim 2 (CHOA + Georgia Tech): Realistic 3D Phantom Model and Human Cadaver Testing - A) Evaluate the steerability and reach of the tools in a clinically relevant realistic 3D phantom model: We will use 3-D printing to create various models of the brain depicting the geometry and anatomic details of both healthy and diseased brains; B) Evaluate the functionalities of the tool tips: we will test the actions and responsiveness of our instruments and designs through cranial nerve and blood vessel dissections in cadaveric heads. This highly innovative and interdisciplinary project combines expertise in surgical robotics (Desai - BME, Georgia Tech), micromachining (Melkote - ME, Georgia Tech), and neurosurgery (Chern - Children's Healthcare of Atlanta (CHOA)) to develop steerable endoscopic tools for neurosurgery. Technological advancements in this project will significantly enhance the surgeon's ability to treat complex cranial diseases via endoscopic surgery.